Electrically actuated gun mount



May 29, 1945. s. E; MCFARLAND ELECTRICALLY ACTUATED GUN MOUNT Filed May6, 1943 6 Sheets-Sheet 1 May 29, 1945. s. E. M FARLAND ELECTRICAL'ILYACTUATED GUN MOUNT 6 Sheets-Sheet 2 Filed May 6, 1943 May 29, 1945. s.E. MCFARLAND 2,377,091

ELECTRIGALLY ACTUATED GUN MOUNT Filed May 6, 1943 I 6 Sheets-Sheet 3Inventor Silas Edamldfllfrland fiawaoz ih WW 29m May 29, 1945. sMCFARLAND 237L091 ELECTRICALLY ACTUATED GUN MOUNT Filed May 6, 1943 6Sheets-Sheet 4 Inventor was ram M'wnd in WW EM y 29, 1945. s. E.MCFARLAND 7,

ELECTRICALLY ACTUATED GUN MOUNT Filed May' 6, 1943 6 Sheets-Sheet 5 kszzaafdwdm /ar May 29, 1945- s. E. M FARLLAND ELECTRICALLY ACTUA'iED GUNMOUNT Filed May 6, 1943 6 Sheets-Sheet 6 Patented May 29, 1945ELECTRICALLY ACTUATED GUN MOUNT Silas Edward McFarland, Chicago, Ill.Application May 6, 1943, Serial No. 485,903

Claims. (Cl. 89-375) .This invention relates to gun mounts for aircraftand it has for its main or general object to provide a gun mount whichpermits the gun to perform all the required movements while directedfrom the pilots seat.

It is well known that in fighter planes manned by the pilot alone or byva very small crew it has proved to be desirable to have guns, especiallymachine guns, mounted in or on or below the wings, which are not mannedbut which are operated from the pilots seat or from some seat closethereto, so that the essential movements of the gun have to be performedby remote control. The pilot has to be provided with several means foreffectively using the guns which are mounted beyond his reach. The gunshave to have a. fixed position first, and when in this position they arepointed by the airplane itself and are fired when the pilot thinks thatthe airplane is at the desired position as regards azimuth andelevation. Rapidly firing guns, such as machine guns may moreover befired while they are rapidly moved to and fro or oscillated and in thiscase they cover a zone in front of them whilethe airplane simply movestoward the said zone, finally the gun may be pointed in the usual waydirectly or by remote control.

The present invention is mainly concerned with the two first-mentionedmethods and does not include or describe the usual method of pointingthe guns by remote control or otherwise although these methods may beemployed in addition to the two methods already mentioned. Theinvention; therefore, has for its object to provide means foroscillatingthe guns so as to cover a zone in front of the plane as theyfire, thereafter, to return or stop the guns in their predeterminedcentral position and to lock them in this definite position in whichthey are ready for being fired straight forwardly in substantialparallelism with the longitudinal axis of the plane, the latter asalready mentioned being in this case the means for pointing the gunstoward the target.

Other objects and advantages of the invention will become apparent tothe reader of the following description.

The various mechanisms for efiecting these movements of the guns arebest described in connection with a modification of the invention shownin the accompanying drawings, in which:

Figure 1 is a fragmentary top plan view of a fighter plane showing oneof the improved gun mounts on each of its wings. I

,Figure 2 is a fragmentary side elevational view of the gun mount,showing a gun thereon and apart from an aircraft.

' Figure B is a top plan view of the gun mount with the gun or gunsremoved.

Figure 4 is a longitudinal vertical sectional view taken on the line 4-4of Figure 3.

Figure 5 is a transverse vertical sectional view taken substantially onthe line 5-5 of Figure 2. Figure 6 is a horizontal sectional view takensubstantially onthe line 6-6 of Figure 2.

Figure 7 is a horizontal sectional view taken substantially on the line1-1 of Figure 2.

;. Figure 8 is a horizontal sectional view taken substantially on theline 8-8 of Figure 2.

Figure 9 is a vertical sectional view taken substantially on the line9--9 of Figure 2.

Figure 10 is a diagrammatic view showing the electrical connectionbetween the electrical elements involved.

Referring to the drawings wherein like numerals designate like parts,it, can be seen that numeral 5 generally refers to a conventionalaircraft structure including a fuselage 6 and wings I, l.

In employing the presentgun mount which is generally, referred to bynumeral 8 and one of which is installed in each wing .l, 1 some slightaccommodation for the mount will haveto be made in the wing in orderthat the mount proper will be lower than the top skin of thecorresponding wing so as to lessen as much as possible air resistance.It is preferable that each gun mount 8 carry a pair of machine guns 9,9.

The gun mount 8 includes a base plate [0 spacially above which is held aplate H by means of posts l2. On. the base and adjacent the forwardportion thereof is an electric motor l3 22 projectingupwardly therefromand through a longitudinal slot 23 in a supporting frame 24 for the guns9, 9; the latter is rotatably mounted on a post 43 and may swing in aplane which is parallel to the plane of the base l0. It is preferablethat the edges of the frame 24.8.1, the slot23 be formed with a rib toaccommodate a rises a stub shaft 4|.

cured by a clamp ring 42 to'a post 43 upon which under the brake andthis comprises a sleeve 29. p

of insulating material fastened on shaft which carries a sleeve ofconductive material denoted by numeral 36'. This sleeve is a cylinderabout 270 complete, the remaining segment being in the form of an insert3| of insulationagainst which a contact 32 normally engages when the.

gun mount is in straight forward position. A stationary arcuate-shapedcurrent conductor 33 partly straddles the semi-cylinder and has contactmembers 34, 35 at the ends thereof for wiping engagementtwith theconductive semicylinder 30. I The conductor 33 is supported by asuitable bracket 36 and the contact 32 by. a suitable bracket 31. y p

In Figures 2 and 4, numeral 38 denotes a lock mechanism for the mount.

Numeral 39 generally refers to relay control means and this is housed inabox 40 from which Thisibox is suitably sethe gun supporting frame 24 ishorizontally swingable.

. The locking meansfor the guns designed to hold them in a definitecentraltposition in which theyare either parallel to the longitudinalaxis of the aircraft or are pointing in a predetermined directionconsists mainly in two interlocking parts and in means for moving one ofsaid parts into the locking and unlocking position.

One of these-interlocking parts consists of a circular mutilated disk 46whose peripheryv has been cut away over a certain angle, the said out4'! covering a substantial segment. The disk projects from a hub portion5|] seated, but freely rotatable on a stub shaft 4|. The hub portion 50is provided with'an arm 52 projecting laterally froin'the hu b. A holeor opening is made in said arm along a line which forms part of a circle'whose center is formed by the axis of stub axle 4|, said hole serving apurpose which will be explained below.

The; disk 46 forming one of the interlocking parts cooperates with a.tail portion 44 of frame 24 which is projecting beyond the post 43around which said frame may be swung and which forms the secondinterlocking member. The interlocking action between the said two partsis obtained by means of a cut in said tail portion; having the form of acircular segment 45, the center'of the circle being the axis of the stubaxle 4| on which the mutilated disk is mounted. The uncut periphery ofdisk 46 fits more or less snugly into the recess and when this uncutperiphery of the disk fills the cut 45 it is clear that the tail 44 andthe frame 24 cannot be moved. p y The cut 4'! on the disk 46 and thecut-out segment 45 on the tail portion 4410f the frame 24 coverapproximately the same angle when measured around the common centerwhich lies in the axis of the stub axle 4|. Therefore, when the two cuts45,and 4'Ijface each 'other--but solely in this position'of'the disk46--the tail '75- 44 and the frame 24 are free to swing around the axisof post 43, when driven by motor l3.

The means for bringing the two interlocking parts either into thelooking or into the unlocking position consists in an electro-magnet 5|of arcuate shape which is fixed on a circular wall 48 surrounding thestub axle 4| at a. certain distance and which encircles about half ofthe periphery of the said wall. This wall is out along the other half ofthe'periphery at 53 and through this cut the lateral arm 52 of the hub50 may pass. In the hole 54a of the arm 52 an arcuate core 54 is fixedwhich may be drawn into the hollow central portion of the electro-magnet5| andwhich isof such length that even when the is carried by the hub.

Between the wall 48 and the=hub a spiral spring 46 is inserted which hasthe tendency to move the arm 52'into its outermost position in which thecore 54 isdrawn out of the magnet as far as possible as shown in Figure6. This spiral spring 49 is, therefore,tensioned when the electro-magnet5| is energized and moves the arm 52 into the position in which the core54 is housed entirely'in the interiorof the electro-magnet 5|.

The former position corresponds to the locking position in which theframe 24 cannot move. The

latter position in which the electro-magnet 5| is energized correspondsto the released or unlocking position in which the two cuts 41 and 49face each other. and theframe may swing forth and back freely.

At one end of the electro-magnet 5| is a. small switch box 55 in whichis located a pair of contact'spring fingers 56, 51 and a contact finger58. A switch operating member 59 is slida bly disposed through wall ofthe box 54 and is capable of being actuated by the arm 52 under theinfluence of the spring 49.

- At the opposite end of the electro-magnet 5| is a small holdingelectro-magnet 60 capable of holding" the arm 52 in the broken lineposition shown in Figure 8 against the action of the spring when thesaid magnet 60 is energized.

In the switch box 40 is an electro-magnetic relay 6| having an armature62 held by a spring '63 in a position of rest in which relay contactsare closed while relay contacts 64 and 66 are open, the electromagneticrelay being deenergized in this case.

' By means of known retarding mechanisms or simply by properly adjustingthe springs of the contacts or the lengths of the operating members thetwo pairs of relay contacts 66 and 65 do not close and open theircircuits simultaneously, but when the relay is deenergized their closingand opening periods overlap. Switch 65 is already closed before switch66 has been effectively actuated and when switch 66 finally opens at theend of the back stroke of the armature 62 an appreciable period haselapsed during whih both contact switches 65 and 66 hold theirrespective contacts closed. There is thus an interval during which thecircuit controlled by both pairs of contacts is closed.

'Numeral 68 in Figures 2 and 10 discloses a manual controller arrangednear the pilotsor operators seat consisting-of an arm 69 having aspring-presseddetent l operatedby a button. 1 The arm 69 carries acontactor 12 which is engageable with a contact strip 13 or with both ofthe contact strip 13 and the contact strip 14. The contactor 12 alsorides the current supply ring 15 to which a lead-16 from a battery 11con nects.

The contactor and the arm 69 therefore can occupy three differentpositions marked I, II and III in Figure 10. In position I, thecontactor is not in contact with anyone of the contact rings 13 and M.In position II, contact is established between the contact ring 15connected with the battery 77 and contact ring 13 connected with the'electro-magnetic arrangement i and Eli (circuit A) and in position III,contact is established between contact ring and both contact rings 13and-'14 whereby the circuit of the battery 11 is connected both with thecircuit of relay 5| (circuit B) and with the above mentionedelectromagnets 5|, Bil, Figure 10 (circuit A),

In the diagram shown in Figure 10, the com nections explain themselves.A battery H is provided which is connected with contact ring of themanual controller on one hand and with the position finding mechanismand the brake magnet on the other hand.

The contact ring i3 is connected with the circuit A which contains theelectro-magnets 5| and and the contacts 55, 51 and 58in the circuit ofwhich indicator lamps 3!), 83 are inserted to indicate the position ofthe arm 52 and of the disk 46. The contact ring M is connected with thecircuit B containing the relay 6|.

The operation and the arrangement is the following:

Let it first be assumed that the pilot wants "to have the guns in theirpredetermined position in which they are centrally adjusted with the gunaxes in parallel to the longitudinal axis of the plane (or in such otherposition which may have been selected). The hand lever 69 of thecontroller is in this case moved into position I. That the guns are nowlocked in their predetermined central position will be apparent from thefact that in this case none of thetwo circuits A and B are connectedwith the tension side of the battery 11. The battery'l'l is, therefore,merely connected by lead 90 withthe contact member 35 and with relaycontacts which are closed when the relay is deenergized. The connectionwith contact ring 35 has the effect that wherever the guns happen to bewhen. this lever of the manual controller was moved to position I itwill be moved to the central predetermined position and will be lockedin this position.

Assuming, for the sake of explanation, that the gun and the frame 24have been turned to the right (Figures 3 and 7) and are staying in thisposition when the hand lever of the controller is moved then the slot 23of the frame 24 and the pin 22 will also have been turned to the rightand will not occupy the required central' position which is thelongitudinal axis of the arrangement in the example illustrated.

The deviation from the correct central positionmanifests itself throughthe relative. displacement of contact member 32 with respect to aninsulating portion of ring 30. The said contact member now rests on aconducting portion of ring 30 and a circuit is thereby closed frombattery 11 over lead 90 to contact piece 35, contact sleeve 30, contactmember32, lead 84, relay 6| and to ground.

-Electro-magnetic relay 6| will, therefore, be;

operated-and will close contacts 64 thereby closing a further circuitover lead 85 to motor I3. The motor will start. to rotate the gun bymeans orgear wheels l5, l6, |8,' l9and by means of the shaft2ll, thedisk 2| and the pin 22. The rotational movement will continue until thecontact piece 32 rests on the insulating part of sleeve 30, in whichcase the circuit will be broken. Asthe insulating segment facesthecontact piece 32 only when the slot 2| and the pin 22 are located in thelongitudinal axis of symmetry of the arrangement of the gun, whateverits original position, is brought to the required central positionwhenever the contact lever 12 is brought into the position I by thepilot.

When the electro-magnetic relay 6| is deenergized the brake magnet 28 isoperated. This operation will be described below in connection with themoving of the contactor 72 to position III.

When the hand lever of the controller is moved to the positioncorresponding to position I of contactor T2 the, circuit A isdisconnected. Therefore, electro-magnet 5| is deenergized and arm 52 isrotated by spring 49 until it rests on rod 59. Disk 66 which isconnected with arm 52 has been rotated to the position shown in Figure 3where it locks the tail portion 44 of frame 24. It is, therefore, seenthat when the contactor 12 is turnedto position I the gun is moved to,the center'position and is locked in thisposition. Assuming now that thepilot wants to unlock the guns and that he turns the hand lever so as tomove the contactor 12 from position I to position II whereby circuit Awill be connected with the battery 11. With the contactor in position Ithe arm 52 or disk 46, as described, was resting on contact 59 under theinfluence of spring 49 with the core 54 drawn out from the interior ofthe electro-magnet 5| and the disk 46 looking the tail 44 of the guncarrying frame 24. When the switch arm 12 is now moved to position II,the pilot gets a signal at indicator showing that the circuits are inorder. The electro-magnet 5| is energized and when circuit A isconnected with the battery and the core 54 (Figure 8) is drawn into thehollow interior of the electro-magnet 5|; the arm 52 moves in thedirection of a clock against the action of spring 49 until it reachesthe stop formed by magnet 5|]. Magnet 6!! is arranged in parallel withelectro-magnet 5| and is, therefore, energized at the same time. Whenarm 52 arrives at the stop it will, therefore, be held against theaction of the spring by the combined forces of magnets 5| and 60.

Indicator 80 after having given a short signal isextinguished when thearm 52 begins to move, while indicator 83 now announces the operation ofthe magnet and the unlocking of the gun.

The movement of arm 52 is transmitted to the hub 50 and to the disk 46and the latter now assumes the position in which the cuts 41 and 45 arefacing each other. Tall 44 is, therefore, free to move in any desireddirection.

The gun may now be moved by remote control to-any desired position. Thisstructure and arrangement, if provided, is, however, no part of thepresent invention. Unlocking of the gun is however also necessary as apreliminary step guns in which the front or the contactor lever 12occupies position III. It will be noted that this position can only bereached by turning the lever through position II, in which the gun isunlocked. The moving of contactor lever 12 to position III connectscircuit B containing relay 6 lwith the battery. The said relay will,therefore, operate and will attract its armature 62 thus closingcontacts 64 and 66 and opening contacts 65 as already explained.

The contact 64 closes the circuit of the motor l3 which runs from groundover lead 85 to contact 64 and from there over 84, l2, 15 to battery 11.The motor l3 by means of gears l5, l6, l8, l9 rotates disk 2| and pin 22and thereby causes a rapid to and fro swinging movement or oscillationof the guns around the pivot 43.

This action continues until the pilot decides to stop it. In this casehe moves the lever 12 back to position I. The operation, when contactor12 has been moved to this position has already been explained and it wasmentioned that whatever th position of the gun when the lever is somoved the gun is automatically brought into its middle or centralposition by the action of the contact members 33, 34, 35, 30 and 32. Ithas now to be explained how the brake magnet 28 will prevent anoverrunning of this position so as to avoid a pendulous movement inwhich the gun comes only to rest after a while by virtue of friction.

It has been explained that the deenergization of relay 6| occurspractically in three phases: the first phase is that in which thecontacts 64 and 66 are closed while the contact 65 is open. This is thefirst phase that is part of the deenergization. The circuit connectionin this phase is that already explained in which the motor circuit isclosed while the brake magnet circuit is open at 65. During the secondphase the contacts 64 have been opened While the contact 66, due to aretarding appliance or to the arrangement of the arm operating thecontactor, is still closed, while contact 65 has already started toclose. Therefore, the circuit of the electric motor I3 is deenergizeclwhile the circuit of the brake magnet 28 is now closed, the connectionbeing made over lead 90 and 9| and over contact springs 65 alreadyclosed, and over lead 92, brake magnet 28, lead 93 and contacts 66 stillclosed to the ground.

This phase, of course, lasts only for a short time, although it may bestretched by a retarding device to any length which may be necessary. Ashort energization of the magnet 28 occurs, the brake is applied to thedrum and thereby the gun frame 24 is arrested in the proper position.The latter position is forcibly attained for if the gun were not in theproper middle position the relay 6! would not be deenergized. It wouldstill receive current over contact 32 sliding on a conducting part ofring or sleeve 30 and lead 84 connected therewith whatever the positionof the lever 12.

The relay 6i can, therefore, be deenergized only when the middle orcentral position of the gun has 'been reached and consequently the brakecan only be applied in this position which is also the proper positionfor locking the gun.

Locking occurs as described in connection with the moving of lever 12 toposition I.

While the foregoing specification sets forth the invention in specificterms, it is to be understood that numerous changes in the shape, sizeand materials may be resorted towithout departing from the spirit andscope of the invention as claimed hereinafter.

Having described the invention, what is claimed as new is:

1. In a gun control system for the remote control of unmanned guns,adapted to be fired either in a predetermined central position or duringpermanent rapid oscillation covering the zone in front of the gun, aremote control arrangement comprising driving means for rapidlyoscillating the guns and a gun frame oscillated by said driving means,means for locking said gun frame in its predetermined central position,mechanical means for bringing said locking means into and for holdingsaid locking means in their operative locking position, electro-magneticmeans .unlocking the said gun frame so as to permit free oscillatingmovement of the same, and hand operated remote control means for makingthe driving means operative and for simultaneously operating theelectro-magnet means for unlocking the gun frame locking means.

2. In a gun control system for the remote control of unmanned guns,adapted to be fired either in a predetermined central position or duringpermanent rapid oscillation covering a zone in front of the gun, aremote control arrangement comprising driving means for rapidlyoscillating the guns and ,a gun frame oscillated by said driving means,means for locking said gun frame in its predetermined central position,mechanical means for bringing said locking means into and for holdingsaid locking means in their operative locking position, electro-magneticmeans for unlocking the said gun frame so as to permit free oscillatingmovement of the same, position controlling means associated with the gunframe, electro-magnetic means operated by remote control for making saiddriving means operative,

said position controlling means operating in parallel to the aforesaidelectro-magnetic means to make said driving means operative fordetermining the correct position.

3. In a gun control system for the remote control of unmanned guns,adapted to be fired either in a predetermined central position or duringpermanent rapid oscillation covering a zone in front of the gun, aremote control arrangement comprising driving means for rapidlyoscillating the guns and a gun frame oscillated by said driving means,position controlling means associated with said gun frame, means forlocking said gun frame in its predetermined central position and meansfor bringing said locking means into operative locking position when theposition controlling means have brought the gun frame into thepredetermined central position, while holding said locking means out ofengagement with the gun frame when the driving means oscillating the gunframe are switched in by the hand operated remote control circuit.

4. In a gun control system for the remote control of unmanned guns,adapted to be fired either in a predetermined central position or duringper,- manent rapid oscillation covering a zone in front of the gun, aremote control arrangement comprising driving means for rapidlyoscillating the guns and a gun frame oscillated by said driving means,means for locking said gun frame in its predetermined central position,said means comprising a projection on said gun frame provided with acut, a locking disk entering said out and provided itself with a cut ofa length corresponding to that of the locking projection, mechanicalmeans for holding said disk in its locking position,

electi e-magnetic means for rotating the disk into the position in whichthe two cuts are facing each other, and a hand operated remotecontroller for energizing said electro-magnetic means concurrently withthe driving means oscillating said gun frame.

5. In a remote control system for guns as specified in claim 2, positioncontrolling means consisting of a sleeve having an insulating peripheralsegment inserted into an otherwise conducting 10 surface, said sleevebeing mounted on the shelf oscillating the gun frame, means forsupplying the conducting surface with current, a sliding contact on saidsleeve, the current through said position finding device beinginterrupted when the sliding contact faces the insulating portion, thelatter being arranged on said sleeve in accordance with the position tobe occupied by the shaft.

SILAS EDWARD MCFARLAND.

